Adhesion of layers to one another typically relies on surface morphology and bonding strength between molecules or atoms on both side of interface. For many materials, covalent or metallic bonds provide excellent adhesion, and care must be taken to avoid contaminants between two materials. Often, this bonding strength is weak, resulting in de-lamination of layers. This is especially difficult to avoid when chemically inert materials such as glass or Teflon have to be bonded to one another. In that case, it is desirable to modify geometry of the bonding interface to increase adhesion of layers.